Citing Matthew 7:20 (“Wherefore by their fruits ye shall know them.”) Mormons challenge us to “inspect the fruit” of Joseph Smith. So I did, and this is what I found:

While claiming that God demanded that he do it, he had at least 44-wives, about a third of them teenagers, (the youngest ones being two 14-year old girls) daughters of leading members of his church, and about another third of them already the wives of living husbands who also were prominent members of his church.
(see official LdS Church website “Plural Marriage in the Church of Jesus Christ of Latter-day Saints”)
He brought forth the Book of Mormon via the occult practice of scrying (the peep stone in a hat) while again claiming that God told him to do it.
(see official LdS Church website, “Book of Mormon Translation”; also see Wikipedia, “Scrying”)

He deceptively claimed that his contrived “divinely inspired” translation of a common Egyptian “Book of Breathings” funerary papyrus was a legitimate translation of the source text.
(see official LdS Church website, “Translation and Historicity of the Book of Abraham”)
He declared, “I will be to this generation a second Muhammad, whose motto in treating for peace was the Alcoran [Koran] or the Sword. So shall it eventually be with us Joseph Smith or the Sword!” (Joseph Smith, October 14, 1838). That, along with Sidney Rigdon’s (June 17th, 1838) “Salt Sermon”, were key provocations for the 1838 Mormon War in Missouri.
(see official LdS Church website, “Peace and Violence Among 19th Century Latter-day Saints”; also see Wikipedia, “Salt Sermon”)

He added and removed biblical text from the Bible even though there was no original language manuscript for the changes. He even went so far as to remove an entire book (The Song of Solomon) from the biblical canon.
(see official LdS Church website “Song of Solomon”; also see official LdS Church History website, “Revelations in Context: Doctrine and Covenants, Joseph Smith Translation”)
He ordered and coerced his fellow Mormon leaders to engage in illegal polygamy with him. And, oh by the way, polygamy was illegal everywhere the Mormons practiced it.
(see official LdS Church website, “Plural Marriage in the Church of Jesus Christ of Latter-day Saints”; also see MormonThink website “Polygamy”)

He taught the blasphemy that God was once a man. And that further taught that good and faithful “worthy” Latter-day Saints can likewise be exalted to godhood.
(see official LdS Church website “Becoming Like God”)

He plagiarized the pagan “Mother in Heaven” doctrine and claimed that is was from God.
(see official LdS Church website, “Mother in Heaven”)

He boasted that he was greater than Christ and the Apostles when he said, “I have more to boast of than ever any man had. I am the only man that has ever been able to keep a whole church together since the days of Adam. A large majority of the whole have stood by me. Neither Paul, John, Peter, nor Jesus ever did it. I boast that no man ever did such a work as I. The followers of Jesus ran away from Him; but the Latter-day Saints never ran away from me yet.”
(see History of the Church Vol. 6, p. 408-412, or Millennial Star No. 42 Vol. 23 p. 672-674, also see Utah Lighthouse Ministry website “Joseph Smith’s Boasting and Polygamy Denial Sermon”)

He publicly lied when he denied that he was practicing polygamy in a sermon on Sunday, May 26, 1844. Specifically, he said, “What a thing it is for a man to be accused of committing adultery, and having seven wives, when I can only find one.” And he said this while at least sixteen (16) of his polygamous wives were still members of his church and most likely in attendance.
(see History of the Church Vol. 6, p. 408-412, or Millennial Star No. 42 Vol. 23 p. 672-674, also see Utah Lighthouse Ministry website “Joseph Smith’s Boasting and Polygamy Denial Sermon”)

He taught moral relativism. For example, he once said, “That which is wrong under one circumstance, may be, and often is, right under another… Whatever God requires is right, no matter what it is, although we may not see the reason thereof till long after the events transpire. If we seek first the kingdom of God, all good things will be added. So with Solomon: first he asked wisdom, and God gave it him, and with it every desire of his heart, even things which might be considered abominable to all who understand the order of heaven only in part, but which in reality were right because God gave and sanctioned by special revelation.”
(see History of the Church, 5:135)

He violated state and local law by assuming every top ranking political office in Nauvoo, Illinois from Justice of the Peace to Mayor. This was done thanks to his absolute control over a sycophantic City Council who simply gave Smith whatever he asked for or demanded. The result was that he was able to ignore every writ of Habeus Corpus and/or Arrest Warrant that crossed his desk that was related to crimes for which he had been legally indicted outside of the city or state.
(see John S. Dinger, “Joseph Smith and the Development of Habeus Corpus in Nauvoo 1841-1844”, Journal of Mormon History, vol. 36, no. 3 (Summer 2010), pp. 135-171)

He ordered the Commander of the Nauvoo Legion to march on the Carthage Jail where he was being held a free him and his brother Hyrum from jail. This would have been an act of treason and sedition under State and Federal law which the Commander wisely ignored. (see Allen J. Stout, “Manuscript Journal, 1815-89”, p. 13; also see Thoma B.H. Stenhouse, “The Rocky Mountain Saints”, Kindle Locations 2698-2725), and; Fawn M. Brodie, “No Man Knows My History (Illustrated): The Life of Joseph Smith“, Kindle Locations 8848-8854)
He brought forth countless contrived “revelations” in the voice of Christ claiming that Christ was speaking through him – even though many of these revelations contradict Christ’s own words in the Bible.
(see Wikipedia, “Doctrine and Covenants”. Also, see the author’s article, “Revelation by Numbers: Introducing “The Joseph Smith Formula” on this website)

He claimed to restore and repair the allegedly “corrupt” text in the Bible via his “Inspired Version” translation of the Biblical text. Yet 99% of the text of the 1769 American Edition of the KJV Bible that he worked from remained unchanged.
(see Wikipedia, “Joseph Smith Translation of the Bible”)

He secretly plagiarized directly from Adam Clarke’s, “Commentary on the Bible”, in producing his aforementioned “inspired” translation of the Bible while simultaneously claiming direct, divine, inspiration for the changes that he made to the Bible.
(see Haley Wilson and Thomas Wayment, “A Recently Recovered Resource: Rethinking Joseph Smith’s Bible Translation”, Brigham Young University, 2017)

He ordered an assassination on Governor Boggs of Missouri by his private bodyguard, Porter Rockwell. Thankfully it failed even though Governor Boggs was wounded.
(see Wikipedia, “Attempted Assassination of Lilburn Boggs”)

In violation of the First Amendment of the US Constitution and Illinois state property laws, he had a private printing press destroyed because it was telling the truth about his secret polygamy and abuse of political and ecclesiastical power in Nauvoo.
(see Wikipedia, “Nauvoo Expositor”)

On June 18th, 1844, in violation of Federal and Illinois sedition and treason laws, he illegally mustered the Nauvoo Legion (his private army that was bigger and better armed than the Illinois State Militia) and declared Martial Law in Nauvoo in case the State of Illinois should attempt to arrest him for his destruction of the printing press.
(see Wikipedia, “Death of Joseph Smith”)

He defrauded his own church members out of monies – even entire estates – via the fraudulent Kirtland Safety Society.
(see Wikipedia, “Kirtland Safety Society”)